Hi @Jonas_George ,
This looks very familiar to what I ran into a few years ago: Forms not downloading or rendering on reverse-proxied, tunneled ODK Central server
Have you looked into that thread to see if any of the suggestions there work?
Additionally, this page in the documentation may also help.
A couple of questions:
- Can you download forms using a mobile device? This will tell you if it is limited to Enketo or generally an issue with the XLSForms.
- Have you tried looking at the docker compose logs to see where the error originates from?
Best of luck!